The high energy and power that are found in some laser beams offer a tool for noninvasive alterations of anterior intraocular tissue. Specifically, iridotomy and trabeculotomy are possible. Such surgery has importance for glaucoma patients because of potential improvement of favorable surgical outcome statistics and reduced surgical morbidity. This project has as its aim a systematic evaluation in simian (rhesus) eyes of laser effects and the application of promising systems and procedures to human glaucoma eyes under controlled conditions. Current work is directed to obtaining a proper Q-switched ruby laser system and to initial testing in monkey eyes.